Jefferson Lab Hall C (and Hall A)
Cryogenic Target System
Target
Systems: Hall C Live
Status & Hall A Live
Status
12 GeV Standard Pivot Targets
(Updated August, 2016)
Hall
A target webpage
Target
Training Talk: (online
version) (pdf) or (ppt).
Target archiver/logger display
EPICS WEB: Check
vacuum, FSD, Raster, etc. from anywhere
Target Training Schedule: When and
where to acquire your target training.
List of 12 GeV trained target operators
Link to
current target configuration (thicknesses, drawings, encoder positions, etc.)
J/Psi Expt. Bremsstrahlung Radiator: description & procedures (pdf file)
Current
Limits (Operational Restrictions) on the Targets
1)
For new Target Operators (TOs):
a) Go through the online
training slides (PH019a).
i) Take the short test (PH019T)
based on those training slides to indicate you understood the material. You
have to get 12 of the 16 questions right to pass.
b) Sign up for practical
training in the counting room with a target expert on a cold tgt (PH019b).
Takes about 1.5 h.
c) Shadow any trained TO for a
few hours while they are on shift in the counting room to familiarize yourself
with your actual shift duties (easiest as a 3rd).
d) Email one of the 3 target
experts when you`ve done all that, and let us know who you shadowed. At that
point we`ll add your name to the list of trained TOs.
2) For
TOs that were trained in 6 GeV era:
a) Go through the online
training slides (PH019a).
b) Ideally also take the short test
(PH019T),
but this is optional if you`ve already been trained.
c) Sign up for practical
training in the counting room with a target expert on a cold tgt (PH019b).
Takes about 1.5 h.
d) Email one of the 3 target
experts when you`ve done all that. Then we`ll add your name to the list of
trained TOs.
3)
For Hall A tritium:
a) Must be cryotgt trained as
described above (PH019a
& PH019T)
b) Must acquire special T2
training from Dave Meekins (PHY020)
Older Experiments:
12 GeV Era Standard Pivot
Targets
(Updated
August, 2016)
Target
Training Talk: (online
version) (pdf) or (ppt).
Are
you target trained for 12 GeV?
Check
your SAF003 status (Hall A/C Cryotarget Operator Training).
Hall
A target webpage & Hall A Live
Status
Hall C Live
Status
- Hall C Documents:
- Target operator essential responsibilities
: A list of everything you are supposed to know how to do. Includes
expert phone/pager numbers.
- Target
operator How-tos: A brief explanation of how to do those things
you're supposed to know how to do.
- Control
System (GUI) Guide: A newly updated (Aug. 2016) “Users Guide to the Hall C CryoTarget” GUIs, written by Chris
Keith. Includes links to more detailed information.
- Hall C
Cryo-Target Manual (old... no ancient. Completely out of date but
still a marginally useful reference for some things)
Or download: (pdf) or (ps) - Warmup/Cooldown
procedure (for experts) and an ESR Simplified Flow
Sheet. Actually in the 12 GeV era, the target group cools down and
warms up the target directly with the ESR liaison. MCC is no longer
involved and these procedures are no longer used.
- Target
Problems (FAQ) and useful
logbook entries
- Hydrogen
Target Safety Assessment Document
- EXPERTS - Names, pagers, phone numbers of who to call
if you need help on the target.
|
Target Expert |
Work |
Cell |
|
Silviu
Covrig |
6410 |
(843)
697-1753 |
|
JP
Chen |
7413 |
(757)
218-0722 |
|
Chandan
Ghosh |
6271 |
(757)
342-4035 |
|
Dave
Meekins |
5434 |
(757)
968-9076 |
|
Chris
Keith |
5878 |
|
|
Chris
Carlin |
5971 |
|
- Fall 2017
- Hall C Target configuration file
(note: the raster halo target replaced the BeO in this list)
- Hall C Target drawing
- March 2014 Hall A
Commissioning:
- Heater: New resistive wire
heater for Hall A: 13.8 Ohms warm
- Heater Power Supply: New TDK-Lambda
supplies, 150 V, 10 A.
- Goal Parameters -
Loop1=LH2 (19 K), Loop2=Spare, No Loop3.
- Targets:
- 15 cm Cells, 10 mils
thick, 3 inch i.d.
- Entrance window is 7
mils thick.
- 15 cm dummy tgts
- 5 foil optics tgt
- Solid Tgt Ladder: MT
MT BeO C hole C
- Wire target?
- Cell drawings
- Graphs of P_beam vs I_beam , and of the auxillary high power
heater pot setting vs HPH power (same with
bigger scale here )
·
Current
Limits (Operational Restrictions) on the Targets
- Hall C
logbook (the new one)
- Target
archiver/logger display
- EPICS
dictionary - A list of the target's EPICS variables, with
descriptions, to help you find things with the archiver.
- Gas flow diagram for the Hall C target system: Best
one in jpg, OR in ps: (part 1)
and (part 2)
- Optics Sled (mechanical
drawing)
- Useful references:
- LH2/LD2
densities and Energy loss
- Thermophysical
properties:
- of para-hydrogen
at 24 psia
- of deuterium
at 24 psia
- of helium
at 1.2 atm near 15K
- Other Useful Links (JLab links)
- Documents:
Online Target Training Test: http://www.jlab.org/div_dept/train/Q-weak/SAF112Q/index.html- The
Qweak target design and safety document: A comprehensive document
describing the details of the target design and safety calculations.
- The Qweak target training
requirements: The novel training requirements for Qweak target
operators.
- A list
of Qweak collaborators who are target trained, and when they
completed each part of their training.
- Qweak target essential
responsibilities: A list of everything you are supposed to know how
to do.
- Qweak Target
operator How-tos: A brief explanation of how to do those things
you're supposed to know how to do. (Still under construction).
- Qweak LH2 target OSP.
- Qweak pump and
procedures: Powerpoint file showing procedures schematically,
or step-by-step
procedures in a word file.
- Checklist
for the HMS valve configuration during Qweak
- Qweak target gas
handling procedures. For experts only.
- Control System
(GUI) Guide. This is for the old control system. A new one for the
Qweak GUIs has not yet been written.
- Warmup/Cooldown
procedure (for experts) and an ESR Simplified Flow
Sheet.
- Draft of the cryo
group's cooldown
procedures for Qweak.
- Target
Problems (FAQ) and useful
logbook entries.
- MCC's Qweak ion chamber
functionality
procedures
- MCC's Qweak ion chamber
calibration
procedures
- Some pictures
of the target
- Emergency
Procedures (quick reference):
- Manuals:
- 6961
controller manual for the target
lifter.
- Lakeshore 218 manual for the
temperature controllers.
- Turbopump manual (2nd half is in
English). My "How-to" reset a turbopump.
- Horizontal
motion calibration info from Silviu.
- Pump
controller manual for the LH2 fan/reciculation
pump (Elite microdrive controller).
- Turbopumps:
- The
manual link is on the line above
this.
- A
few sentences of guidance on how to reset a turbopump are here.
- To
check (vacuum and) pump status, bring up monticello (for example, type
/home/poltar/edmmonticello on poltarcc as poltar).
- Then
click the gold button on the vacuum row.
- That
brings up the valve commander. In the upper left corner is a shaded box
with a button labelled "Halls". Click that button to bring up
a menu list, choose the one that says "Hall C (Qweak)".
- Now
you have a GUI (/cs/opshome/edm/vac/VAC_O_hallCQweak.edl) which shows
you the vacuum and the turbopump status at the scattering chamber, the
vacuum dump tank, the downstream beamline, and the upstream beamline.
- You
can request MCC to isolate the scattering chamber vacuum by closing the
upstream valve VBV3H09B and the downstream (16" gate) valve
VBV3H09D. Doing this one valve at a time can help tell you where the
problem might be, but the Qweak vacuum GUI should also tell you- the
turbopump boxes are red if the pump is off, and green if the pump is on.
- It
can happen that the valve to the backing pump closes. Symptoms are that
the vacuum is steadily worsening, but that there is no load shown on the
turbocontrollers. This means the gate valves right at the turbopumps are
closed. The buttons to open (or close) these valves (they go together)
are about chest high, maybe a meter to the right of the backing pump on
the 2nd floor of the blue platform.
- Hydrogen recirculation Pump/Fan:
- Links:
- Qweak
document database, target section.
- Hall
C logbook.
- Qweak
wiki
- Qweak
webserver
- Qweak
homepage
- Qweak
shift schedule
- Qweak Elog
- Qweak
glossary
- Hall
C survey reports
- EXPERTS - Names, pagers, phone numbers of who to call in
what order in a crisis. Also contains other useful phone numbers (MCC,
RadCon, RC, PD, etc.).
- Notes
on paging:
- When
you page someone, it generally takes a couple minutes for the page to be
received, and another minute or two for that person to get to a phone.
If you have not gotten a call back within 5 minutes, assume the page was
not received and try another number or the next person on the call
list.
- To
page:
- By
email: send an email to (for example) smithg-page@jlab.org.
- By
phone: dial (9) 435-page (435-7243) and then when prompted enter the 10
digit phone number, for example 757 327 5443 followed by the pound key.
- From
a web browser: go to http://www1.jlab.org/mis/staff/staffsearch.cfm
, search for the person, and click on the "click to page"
field.
- On-Call
list:
- Goal Parameters -
- Temperature:
20 K ± 0.01 K.
- Pressure:
30-35 psia (~20 psig).
- Pump
frequency: 30 Hz.
- Minimum
heater power: 100 W.
- Raster
ON at 4x4 mm^2.
- Note:
- Cooling:
- Qweak
cooling power budget, and graph of coolant mass
flow versus cooling power required.
- Qweak
cryocan connections.
- Qweak
ESR scheme.
- P&I drawing of target cryo
connections & gas panel.
- Msc:
- Target & Window Thicknesses:
- The
LH2 target is ~34.5 cm thick (4.0%) of LH2.
- The
upstream target cell window is 3.8 mils thick 7075 aluminum. (#7).
- The
downstream target cell window was 4.4 mils 7075 aluminum in the 15 mm
diameter nipple, and 21-24 mils thick everywhere else. Because of a leak
that developed right before installation, the "old" exit window
#3 was put in instead, it's around 5 mils thick. More precise
measurements to follow...
- The
downstream dummy tgts were made from the same block of metal as the 4.4
mil window were made from. This is not the same block as the old window
#3 that we are using, however it is the same alloy.
- This
exit window that got replaced at the last minute was one of two that
came in June 2010, it was polished on one side (vacuum side). The
window that arrived with it failed the certification test. We still have
an older window that was not polished as a spare- it got put in at the
last minute. Finally, a new window is now being made so we will have a
2nd spare.
- Solid
target frame dimensioned drawings: Sheet 1 2 3 4 5
- Solid
target geometrical layout cartoon, looking
downstream. Solid target thermometer locations.
- Solid
Target Scheme 3D cartoon, including numbering
scheme
- Solid
target list with thickness measurements, weights, etc.: (Excel file)
- The
vacuum window thickness is nominally 35 mils. See OCE drawing
67503-00098, and this report.
- Dump
window (see OCE drawing 67503-00128): and this report.
- Mildly
useful references:
Standard
Pivot Targets (Spring-07)
- Documents:
- Target
operator essential responsibilities : A list of
everything you are supposed to know how to do. Includes expert
phone/pager numbers.
- Target operator How-tos: A brief
explanation of how to do those things you're supposed to know how to do.
- Control System (GUI) Guide
- Hall C Cryo-Target Manual (old...
out of date but still a useful reference for some things)
Or download: (pdf) or (ps) - Warmup/Cooldown procedure (for experts)
and an ESR Simplified Flow Sheet
- Target Problems (FAQ) and
useful logbook entries
- Hydrogen
Target Safety Assessment Document (word, pdf)
- EXPERTS - Names, pagers, phone
numbers of who to call in what order in a crisis.
·
Current Limits (Operational Restrictions) on the Targets
- Hall C logbook
- Target archiver/logger display
- Gas flow
diagram for the Hall C target system: Best one in jpg, OR in ps: (part 1) and (part 2)
- Gep Target Thickesses for:
- Spring 07
- SP04 (XEMPT-04)
- Spring04 (XEMPT-04) Target thicknessess, pictures,
etc.
- XEMPT- summer 04 temperature calibrations & corrections
- Thicknesses of 1% Targets installed Jan., 2005
- SP03:
- Cell Thickness measurements for the Spring-03
expt.s
- Dummy & cell thickness measurements from D.
Meekins for the Spring-03 expts. in inches.
- Thickness measurements from D. Meekins
for Spring-03, in mm. (Same as above, but in mm instead of inches).
- Optics Sled (mechanical drawing)
- Useful references:
The G0 Target
Experts : who to call in an emergency
Target Training Slides All the slides we
use in the target training course. 
